April 1921

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Features

Man-Killing Insects, The Hudson River Bridge and more

By George Philip Paul

Milk Without Cows

By S. R. Winters

Stopping Our Coal Leaks

By Charles P. Steinmetz

The Sailing Ship's Return

Will the High Costs of Operation Bring In Another Sailing Ship Era?

By John T. Rowland

Bowling On the Green

By William Henry

Cinematography at the Winning-Post

By Alfred Gradenwitz

Succeeding in Scientific Farming

A Survey of the Opportunities Awaiting the Man Who Is Going Back to the Land

By Raymond Francis Yates

The Train Director and his Work

How Hundreds of Trains Are Handled In and Out of a Giant Railroad Terminal

Hydroelectric Power in Argentina

Will the Iguazu Falls Provide the Solution of a Grave Fuel Problem?

By Leonard Matters

A Hospital for Mail Bags

How the U. S. Post Office Department Operates a Factory for Making and Repairing Mail Bags

By S. R. Winters

New Remedy for Healing Wounds

Departments

Departments

Correspondence

Inventions New and Interesting

Recently Patented Inventions

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Digital Issue ?Read or download this issue’s articles online. *A printed copy of this issue is not included. $7.99

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